<!DOCTYPE html>
<html>
<head>
	<meta charset="utf-8">
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<title></title>
</head>
<body>
<div></div>

<script type="text/javascript">
	let str = "<h2>111</h2>"
	let str2 = "111"

	let div = document.getElementsByTagName("div")[0]
	//innerText 以文本形式读写内容

	div.innerText = str
	div.innerText = str2
	console.log(div.innerText)

	//innerHTML 以代码的形式读写内容
	div.innerHTML = str
	console.log(div.innerHTML) //<h2>111</h2>
	console.log(div.innerText) //111
</script>
</body>
</html>